1. Field of the Invention
This invention relates to a feeding and separating system for sheets of material from a stack of sheets such as, for example, a stack of mailpieces, i.e. envelopes, which are then to be fed into a postage meter for placing postage on the envelopes, and in particular to an improved feeder apparatus which accomplishes reliable and efficient separation for individual feeding of documents from a stack of documents even if the documents are of various thickness"" and of various sizes.
2. Description of Prior Developments
The prior art describes many different types of feeding and separating devices. One issue that most of these devices have constantly raised is the fact that it is a particularly difficult part of the design of any stacked document feeder with regard to the separation of documents. It is extremely critical in these devices that documents be passed consistently one by one from the feeder to other equipment in the paper path, such as, for example, a postage meter. An example is where envelopes are fed from a postage meter positioned in a mailing machine. The passage of documents, e.g. envelopes, one by one permits the postage meter to place an imprint of postage on each of the envelopes in a reliable process. It is important that misfeeds such as duplicate feeding of two or more documents at the same time be minimized or completely eliminated. It is also desirable in such equipment that the feeder/separator apparatus be able to avoid the double feeding of envelopes completely while at the same time feed and separate mixed mail, i.e. feed and separate envelopes of varying sizes, thicknesses and dimensions. These various design goals need to be achieved within the constraints of cost and size factors. It is therefore particularly desirable to accomplish these various design goals within a reasonable cost of the product, while at the same time minimizing the number of parts and assembly steps needed to manufacture the feeder/separator in accordance with the features of the present invention.
It is therefore a primary objective of this invention to achieve the above-described advantages and design goals in a feeder/separator apparatus, and thereby describe a feeder/separator apparatus that (i) avoids the double feeding of envelopes; (ii) separates envelopes of different sizes; and (iii) automatically adjusts to the different thickness of the various envelopes being fed.
These various advantages and features of a feeder/separator is achieved in accordance with the features of the present invention by a feeder/separator apparatus for separating and moving sheets from a stack of sheets comprising: an input area for positioning the stack of sheets; a first and second series of rollers for jointly feeding a sheet on the bottom of the stack into an area of the apparatus including a third and forth series of rollers and a first series of belts; a pre-separation brake adapted to act in a pivoting pattern on the first series of belts only, to thereby cause a first stage separation of the bottom sheet; a separating brake adapted to act in a linear pattern on the forth series of rollers only, to thereby cause a second stage separation of the bottom sheet, the pre-separation and separation breaks permitting the bottom sheets to be separated from the stack; and a fifth series of rollers and a second series of belts both being adapted to feed the bottom sheets away from the feeder/separator apparatus in a sheet feed path.